We would know if someone was accumulating because they would have to divulge this info once they reach 5% and then again every time their overall holding goes up by a further 1%.
If someone is specifically trying to force the price down with the intention of a takeover bid, there is a fair spread of shareholders and a majority would have to approve the offer - unless the price is right, I doubt whether many would.
If there was a takeover offer (say by Daiichi Sankyo or GlaxoSmithKline), we'd be doing our maths on things like the upcoming LANI license, future LANI royalties, Relenza Royalties etc and I think most holders would not accept offers below $3.50-$4.00.
BTA Price at posting:
$2.15 Sentiment: LT Buy Disclosure: Held